月: 2023年1月

What Is an SSD?

An SSD is a type of data storage device.

An SSD stands for “solid state drive” and is characterized by the fact that it is a recording device using semiconductors.

Uses of SSDs

In recent years, SSDs have been widely used in office automation equipment. Like hard disks, they are used for data storage. Specific applications are as follows:

• Record storage in servers for office building management.
• Record storage in general household PCs.
• Record storage in office PCs.
• Data storage in surveillance cameras.
• Record storage in cloud servers.

Principle of SSDs

SSDs consist of NAND flash memory, controller, cache memory, interface, etc. NAND flash memory is the part that stores data inside SSDs. MLC for 2-bit data, and TLC for 3-bit data.

SLC has the advantage of high durability, but has a smaller capacity and is more expensive. The controller is the part that performs access control for reading and writing data; NAND flash memory has an upper limit on the number of rewrites, and access control is used to prevent writing only to specific memories.

Cache memory is the part that temporarily caches data, often using DRAM, and can speed up the write process by temporarily storing data. The interface of an SSD is the connection between the SSD and the computer. There are several standards, such as SATA and mSATA.

Other Information on SSDs

1. History of SSDs

HDDs (hard disc drives) have been widely used to store large amounts of data. HDDs record data by reading and writing magnetism on a disk rotating at high speed. While HDDs are simple and inexpensive, they have a drive unit that rotates the disk, making them vulnerable to shocks.

Also, at the time when HDDs were the mainstream, the storage capacity of SSDs was small. As such, HDDs were the mainstream storage medium for office automation equipment. In recent years, however, as SSDs have increased in capacity, they have replaced HDDs in popularity.

2. Differences Between SSDs and HDDs

Both SSDs and HDDs are used as storage media for office automation equipment. However, each has its own merits and demerits based on its characteristics.

Advantages of SSDs:

• Fast data writing and reading
• Faster boot-up when an OS such as on a PC is installed
• No driving parts and no operating noise
• Resistant to shocks

Disadvantages of SSDs

• Expensive compared to HDD
• Fewer high-capacity types are available compared to HDDs
• The maximum number of writes is limited, and SSDs have a limited lifespan.

Advantages of HDD

• Inexpensive, high-capacity storage media can be introduced.

Disadvantages of HDD

• Noise is generated when the disk rotates during operation.
• Low shock resistance; data may be corrupted by vibration, etc.
• Power consumption is higher than SSDs
• Slow read/write speed compared with SSDs

As described above, HDDs and SSDs have their own merits and demerits. Therefore, it is important to use them depending on the application. As an example, one HDD and one SSD may be installed on the same PC.

In this case, frequently used software and OS are written on the SSDs, and videos and images are written on the HDD. This operation allows the PC to be operated as a PC with a large storage capacity as well as fast everyday PC operation and PC startup.

3. External SSD and USB Flash Memory

External SSDs and USB flash memories are both based on NAND flash memory. However, they are read differently on the OS.

A USB flash drive SSD is recognized as a local disk inside the computer. It is not intended for frequent insertion and removal. However, the internal partition settings can be changed more freely than with USB flash memory.

USB flash memory is recognized as a removable disk inside the computer. It is characterized by the availability of inexpensive, small-capacity products. In addition, players and other devices that use USB flash memory may not properly recognize external SSDs.

What Is a V-Belt ?

A V belt is a belt with a V-shaped cross-section that transmits the power of a rotating machine. V belts are less expensive and quieter than chain belting. Its performance is best demonstrated when used with pulleys that match the belt’s specifications. A pulley is a disk with a groove cut in it for the belt to bite into. The V belt requires periodic maintenance due to wear and tear caused by use, as well as stretching of the V belt itself. If left in place, the V belt and pulleys can slip, resulting in abnormal noise and reduced capacity.

Uses of V-Belts

V belt and beltings are widely used in power transmission. They are also used in power transmission in automobiles and in the drive units of fans and blowers. They are also used in a high percentage of agricultural equipment. This is due to their ease of maintenance and low cost of ownership. Depending on the application, multiple V belt and beltings are used to transmit greater power. When replacing the V belt, care must be taken because fingers can easily get caught between the belt and pulleys, resulting in injury.

Features of V-Belts

V belts are one of the power transmission methods. However, it is not capable of performing at its full potential unless the tension is properly adjusted. If the tension is too strong, it can lead to abnormal wear, wear on each rotating shaft, bearing damage, and overloading of power equipment. Conversely, too little tension can lead to V belt slipping noise, reduced capacity, and equipment stoppage due to V belt dropout. The proper tension is determined in the manufacturer’s catalog. It is important to keep the tension within the corresponding standard, which is determined by the pushing force and the pushing allowance times the constant distance between the shafts. A tool called a tension gauge is also used for this purpose and should be carried along when performing maintenance.

There is also the type of V belt that has an uneven surface called a cog. This type is suitable for small pulley diameters. The use of a V belt with a small radius of curvature can solve this problem.

When replacing the V belt and belting, the condition of the pulleys should also be checked; even if the V belt is new, if the pulleys are worn, it will lead to abnormal V belt wear and poor rotation. There is a gauge for pulleys called a groove gauge, which can be used to check the condition.

What Is an XYZ Vacuum Stage?

An XYZ vacuum stage is a precision platform capable of fine movement in three dimensions (X, Y, and Z axes). Equipped with micrometers for precise adjustments down to 0.01 mm, it features multiple screw holes for attaching optical components and can include a magnet for secure placement on optical tables.

Uses of XYZ Vacuum Stages

XYZ vacuum stages are versatile tools for accurately positioning sample holders, heating mechanisms, and optical elements in research and industrial applications. They are particularly useful in laser systems for adjusting mirrors and lenses within the optical path.

Principle of XYZ Vacuum Stages

These stages operate on different guiding systems for movement:

• Cross Roller Guide System: Provides high rigidity and precision with linear contact rollers, minimizing friction and allowing fine adjustments.
• Dovetail Groove Guide System: Offers a cost-effective solution with a simple design, suitable for basic positioning tasks.
• Ball Guide System: Features balls arranged between guides for reduced thickness, high rigidity, and precise control.

Features of XYZ Vacuum Stages

Key features include:

• High-precision positioning with micrometers and cross-roller bearings.
• Compatibility with ultra-high vacuum environments for advanced scientific research.
• High-temperature resistance, suitable for processes requiring baking up to 200°C.

Other Information on XYZ Vacuum Stages

Positioning methods vary from manual adjustments observed through cameras to fully automated systems utilizing visual sensors for enhanced accuracy and efficiency. Applications include semiconductor exposure processes and screen printing, where precise positioning is critical.

What Is an Acrylic Product?

Generally speaking, the term “acrylic” refers to acrylic resin or acrylic fiber.

Although both are called “acrylic,” they have different chemical structures and are completely different from each other.

Acrylic resin was industrialized around 1934 and is still used today as a raw material for plastics in a variety of applications.

Acrylic fiber, on the other hand, is also well-known and was developed around 1950. It has properties similar to wool and is used in clothing such as sweaters.

Uses of Acrylic Products

First of all, acrylic products were initially used for military applications, such as in the canopies of fighter aircraft.

Today, however, acrylic products are used in a wide range of applications, including lighting fixtures, construction materials, electronic components, industrial materials, and acrylic paints.

On the other hand, acrylic products with properties similar to wool are used for sweaters, knitted hats, blankets, and carpets.

In addition, acrylic fiber is used in the industrial field as a filtering material for filtration equipment and in the construction field as a substitute for asbestos.

Characteristics of Acrylic Products

Acrylic products are made by polymerizing organic compounds called methacrylic esters or acrylic esters.

The manufactured acrylic products are durable, heat resistant, easy to process, and impact resistant. However, their greatest merit is their transparency.

For this reason, acrylic products are made into panels and applied to aquariums.

The disadvantage is that the surface is easily scratched. For this reason, it is also applied as a resin for raw materials for paints. However, the paints produced are sold with the claim that they are inexpensive and have short durability.

Acrylic fiber is produced by taking an organic compound called acrylonitrile as a starting material and polymerizing it with other organic compounds.

Those made from 85% or more polymerization of polyacrylonitrile through this polymerization are called acrylic fibers, while those made from 35 to 85% and containing vinyl chloride or vinylidene chloride are called acrylic-based fibers.

The advantages of acrylic products are lightness, moisture retention, and good dyeability; the disadvantages are that they are prone to static electricity.

What Is Acetate?

Acetate is a man-made fiber made from cellulose acetate.
It has a long history, first produced in the United Kingdom after World War I, and then in Japan in the 1950s.

Although there is not much acetate produced in Japan today, it is used in large quantities for clothing in the United States.

Cellulose acetate is chemically synthesized from high-purity wood pulp material and used as fiber.

It is called “semi-synthetic fiber” because the fiber is synthesized from plant fiber (cellulose) of natural pulpwood.

Uses of Acetates

Acetates are used as a fiber product in a variety of situations.

With a unique texture and luster, acetates are used for clothing fabrics, accessories, neckties, curtains, fabric linings, umbrellas, shirts, and more.

They are also used for business wear such as formal wear, casual wear such as sweaters, as well as raincoats and interior fashion goods.

Recently, acetates have also been used to make blouses for women due to their unique luster, taking advantage of the luster of acetate fabrics.

Characteristics of Acetates

Acetates are characterized by their silky luster.
They also have a fluffy texture and feel of woolen fabrics.

The advantages are its high heat retention properties, moderate elasticity, and moisture absorbency.

The tactile quality is that it has a pleasant sensation on the skin. In addition, the fabric is lightweight, making it comfortable to wear.
The elasticity of the fabric prevents wrinkling and is often used for skirts and suits.

Conversely, the fabric softens when heated with an iron, etc., and maintains its shape when cooled, so it is used to make the folded pleats of skirts.

The disadvantage is that the fabric itself is sensitive to friction and heat, so care must be taken when ironing to avoid heat deformation.

In addition, colored fabrics must be handled with care because of the risk of discoloration of dyed fabrics due to automobile exhaust and exhaust gas from oil stoves.

In addition, be sure to avoid contact with light-removing liquids and thinners, which can dissolve acetate fibers.

What Are Aramid Fibers?

Aramid Fiber is a general term for high-performance fibers made of aromatic polyamides. They were developed by DuPont in 1965. In 1974, it was given the generic name Aramid Fiber to distinguish it from nylon.

They are synthesized by polycondensation of para- or meta-phenyldiamine with diamine phthalate.

Aramid Fiber can be classified into two groups, para- and meta-aramid, based on differences in molecular structure. The former has superior mechanical strength, cut resistance, and vibration damping properties, while the latter has superior heat resistance, flame resistance, and chemical resistance.

Uses of Aramid Fiber

Para- and meta-aramid fibers have different characteristics, and are used in applications that take advantage of these characteristics.

1. Para-Aramid Fiber

Para-aramid fibers are used in an extremely wide range of fields, from industrial applications to the aerospace industry. Examples of industrial applications include tension members and ropes for optical fiber. These applications take advantage of the material’s resistance to elongation, while being about five times stronger than steel of the same weight.

In addition, its high resistance to friction is used in applications such as tires and brake pads, which need to withstand long-term wear. Furthermore, because of its cut resistance, it is also used as a fiber for safety and protective goods such as work gloves and bulletproof vests.

In the aerospace field, its heat resistance is also used as a parachute component.

2. Meta-Aramid Fiber

Unlike para-aramid fibers, meta-aramid fibers do not excel in strength. While possessing the same strength, specific gravity and texture as general-purpose polyester, meta-aramid fibers have a high oxygen index, which indicates flame-retardant performance, and do not melt or decompose at temperatures up to 400°C.

Aramid is used in applications requiring heat resistance and flame retardancy, such as firefighting uniforms and aircraft seats.

Properties of Aramid Fiber

1. Para-Aramid Fiber

The strength and high modulus of para-aramid fibers are derived from the strength of the bonds within the polymer. Para-aramid fibers are all-trans, resulting in a molecular backbone with high linearity and flatness.

When para-aramid fiber is dissolved in concentrated sulfuric acid and stretched, molecular chains are first hydrogen bonded to each other, which then chain together to form flat plates. The plates then aggregate with each other by intermolecular forces to form a cylindrical fiber material. The special arrangement of molecular chains and the formation of a higher-order structure result in a variety of properties, including high strength and high elastic modulus.

2. Meta-Aramid Fiber

Because the molecules of meta-aramid fibers are arranged in a zigzag pattern, hydrogen bonds and intermolecular forces are weaker than those of para-aramid fibers, and the strength is comparable to that of polyester and nylon fibers.

On the other hand, they have a relatively flexible structure, and since the benzene rings form a dense structure at high temperatures, they are resistant to decomposition and ignition, and exhibit excellent heat resistance.

They also have excellent chemical resistance to acids and alkalis.

Other Information on Aramid Fibers

Differences Between Aramid Fiber and Carbon Fiber

Carbon fiber is also known as an organic fiber with high strength. Carbon fiber is a material with applications ranging from sporting goods to the aerospace field due to its overwhelming light weight and strength.

However, its conductivity makes it impermeable to electromagnetic waves, and it has the disadvantage of low abrasion resistance. In addition, it is very time-consuming to process, making its cost high. For this reason, plastics with insulating and abrasion-resistant aramid fiber composites are often used for the back panels of smartphones.

What Is Aluminum?

Aluminum, with the atomic number 13 and symbol Al, is a lightweight metal (specific gravity of 2.7). It is extensively used in transportation (vehicles, aircraft, bicycles), sports equipment, packaging, and building materials due to its excellent thermal and electrical conductivity. Its malleability makes it ideal for various fabrication processes, and its corrosion-resistant oxide coating ensures durability.

Uses of Aluminum

Aluminum is pivotal in numerous applications:

• Transportation Equipment: Engine blocks, airplane components, train carriages, and window frames.
• Packaging Materials: Foil, cans, blister packs.
• Building Materials: Window sashes, roofing, handrails.
• Electrical Products: Cables, enclosures, heat sinks, and capacitors.
• Tableware and Cookware: Pots, pans, and utensils.
• Medical Equipment: Artificial joints, implants, and surgical tools.

Properties of Aluminum

Lightweight

Aluminum’s low density is attributed to its large atomic spacing and weak atomic attraction, making it significantly lighter than iron and copper.

• Aluminum: ~2.71 g/cm³
• Iron: ~7.87 g/cm³
• Copper: ~8.96 g/cm³

Corrosion Resistance

The metal forms a protective oxide film naturally, shielding it from corrosion. Yet, certain environments necessitate additional surface treatments.

Conductivity

Aluminum’s exceptional electrical and thermal conductivities are due to its atomic structure and metallic bonds, facilitating efficient electron and heat transfer.

Workability and Plasticity

Its malleability and strength, even when soft, allow for easy shaping through hot or cold working processes, without compromising durability.

Nonmagnetic

Its weak magnetic properties make aluminum suitable for applications sensitive to magnetic interference, such as electronic device casings.

Types of Aluminum

Pure Aluminum

Pure aluminum offers flexibility, processability, and excellent electrical and corrosion resistance with a purity of 99% or higher, though it has limited strength.

Aluminum Alloys

Alloys enhance aluminum’s properties, such as strength and corrosion resistance, by adding elements like copper, magnesium, or silicon.

Aluminum Casting Alloys

These alloys are designed for the casting process, achieving complex shapes with high heat and corrosion resistance.

Other Information on Aluminum

Biocompatibility

Aluminum is biocompatible, posing a minimal risk of allergic reactions or inflammation, thanks to its protective oxide film.

Reflectivity

Its crystal structure and electron arrangement enable aluminum to efficiently reflect light and heat.

Recycling

Aluminum is sustainable, with a high recycling rate for used products.

Electrolyte Reaction

While prone to electrolyte reactions, surface treatments can mitigate corrosion risks, prolonging aluminum’s lifespan.

What Is an Anchor Bolt?

Anchor bolts are screws that fasten wood or metal structural members or equipment to floors or walls.

Anchor bolts can be manufactured by rolling or cutting. Rolling is a manufacturing method that uses plastic deformation to create threads. In contrast, cutting is a manufacturing method in which threads are formed by hand or automatically using a machine.

Compared to cutting screws, thread rolling screws are considered to have higher strength and can be used according to conditions.

Uses of Anchor Bolts

Anchor bolts can be used to prevent equipment and other devices to which they are attached from separating, moving, or tipping over.

For example, if a unit with a drive unit is installed on a frame, vibration is generated when the unit moves on the frame. Since the unit is strongly fastened to the frame, the vibration is transmitted directly to the frame, which shakes in response to the vibration and may move or topple over if the vibration becomes significant.

This situation can be prevented by using anchor bolts to fasten the legs of the trestle to the floor and allow the vibration to escape to the floor.

Principle of Anchor Bolts

Calculate the shear and tensile forces created in an anchor bolt. The allowable shear and tensile forces of the anchor bolt and the allowable pullout force from the concrete are calculated, and the embedment length, material, and thickness can be determined so that the shear and tensile forces of the anchor bolt are not exceeded.

For tension, the smaller of the allowable pullout force from the concrete and the allowable pullout force of the anchor bolt is used. If the allowable tensile force of the anchor bolt is greater than the allowable pullout force from the concrete, the concrete will fail first. Furthermore, if the allowable tensile force of the anchor bolt is less than the allowable pullout force from the concrete, the steel will yield first.

Where earthquake resistance is required for columns, beams, bearing walls, etc., the design must be such that the allowable tensile force of the anchor bolt is less than the allowable pullout force from the concrete.

Types of Anchor Bolts

Anchor bolts have different characteristics depending on the type. The main types are as follows:

1. Internally Threaded Anchor

This is the most common type of anchor bolt. The bolt can be driven into the floor or wall surface with no protrusion on the surface.

2. Anchor Bolt With a Core Rod

Anchors that can be cast directly on top of the object to be fastened. There are several types of anchors such as All Anchor, Best Anchor, Rooty Anchor, C-type anchor, and Tight Anchor.

3. Adhesive Anchor

Also called chemical anchors because they are fastened with an adhesive, there are two types: capsule type and injection type. In the capsule method, a hole is first drilled, a capsule containing adhesive is inserted, and the anchor is driven into the hole, causing the adhesive in the capsule to leak out and fix the anchor in place. On the other hand, in the injection method, the adhesive is injected directly into the drilled hole, and the anchor bolt is then driven into the hole.

4. Welded Anchor

The object to be fastened is fixed by welding. The head part can be directly welded and fixed, and the size is small.

5. Grip Anchor

Can be used for fastening to concrete. The anchor body is driven into the concrete. The anchor body is threaded and the object is fastened when the anchor bolt is tightened.

6. Board Anchor

Board anchors are used to attach components such as hollow structural walls or plasterboard. They can withstand a certain amount of weight and are available in various types. Some types can be installed without damaging the wall and are made of fire-resistant steel. However, many types are non-removable.

7. Anchor for ALC

These anchors are used to attach lightweight foamed concrete panels to metal fittings. They can be used in a wide range of situations, depending on their strength. Anchors for ALC with excellent heat, chemical, impact, and weather resistance are also available.

8. Fastening Anchor

Fasten to concrete as if tightening a screw. Requires hole depth.

9. High-Performance Anchor

Easy installation by simply turning a bolt. Can be installed with power tools, reducing work time.

10. Anchor for Hollow Wall

Can be classified into Amera hanger and IT hanger. Amera hangers have a short roll plate and are suitable for installation in hollow walls, while IT hangers can be penetrated with holding power and do not damage the surrounding area because they work while the installation device is in place.